Inefficient networks, many of which are run continuously, are a major driver of IT equipment’s growing share of total office and household energy use. In February, the Energy Efficient Ethernet Study Group (EEE) was launched to promote technological standards to encourage the use of networks that reduce power consumption by switching rapidly to low speed when idle.
The group is a joint venture between industry body the Ethernet Alliance and the Institute of Electrical and Electronic Engineers, which sets global standards for a range of technologies.
It has the backing of manufacturers such as Broadcom, Applied Micro Circuits Corporation and Cisco, as well as governmental bodies such as the US Environmental Protection Agency and the European Commission.
In an Ethernet Alliance press statement, principal administrator of the Commission’s joint research centre Paolo Bertoldi said improving Ethernet efficiency is "a logical and important next step". It follows on, he said, from EU efforts such as the voluntary code of conduct adopted last summer to improve the energy efficiency of broadband communication equipment.
The EPA said it intends to incorporate the group’s work into its standard-setting Energy Star efficiency programmes.
Mike Berkeley of the US Lawrence Berkeley National Lab said the project offers the opportunity to maximise synergy between the energy, network and computer industries.
Aside from exploring ways to reduce networks’ inherent energy use, EEE intends looking at how networks can reduce energy use by equipment at each end.
Ethernet has been the industry-standard cabled network technology since the mid-1990s. It connects PCs, network printers, servers and other network devices. Ethernet networks commonly have a processing speed of 10, 100 or 1,000 megabits per second. A 10 gigabits per second standard was established last year and an even faster 100Gb/s is expected to be introduced this year.
Each successive standard requires more power to operate and increasingly devices and networks are being left on continuously. The Ethernet Alliance is aware such trends will have to be countered.
It estimates that, in the US alone, 5.8 terawatt-hours of energy are wasted each year through inefficient networks. The global figure could be three times higher, leading to savings of up to £500 million annually.
Reducing network speeds from 100Mb/s to 10Mb/s when idle would save 2 watts per device, according to Mr Bennett. With a corresponding saving for the device at the other end of the network, and multiplied by the thousands of devices linked by some networks, he points out that the savings soon add up.
Because networks in homes are generally less actively used than those in offices, the greatest savings could be made in this area.